The general purpose of this research is to examine ego identity, ethnic identity, and cultural adaptation among minority adolescents, with a focus on both the variables that influence these processes and the ways in which these processes in turn relate to over-all psychological adjustment. A specific goal of this study is to develop a causal model that can explain the ways in which these factors interact and influence each other. The study will also provide descriptive, normative data on identity development in minority adolescents. The research will use a longitudinal design that follows two cohorts of adolescents for three years, with one cohort beginning in eighth grade and a second cohort beginning in tenth grade; thus the study over-all will cover the period from eighth through twelfth grades. The participants will be American-born children of immigrants from three ethnic groups (144 Armenian Americans, 144 Mexican Americans, and 144 Vietnamese Americans). Adolescents will complete questionnaires to assess ego identity, ethnic identity, cultural adaptation, peer interactions, family processes, and psychological adjustment. Parents will complete a brief questionnaire on cultural attitudes and values. The longitudinal design will allow for the testing of causal relationships, that is, the effects of predictor variables measured the first year on outcomes assessed the subsequent two years. Results will be analyzed to test a number of specific hypotheses. In addition, a comprehensive model will be developed to test the interrelationships among the variables. It is expected that family and peer variables will affect the endogenous variables of ego identity, ethnic identity, and cultural adaptation, and that these endogenous variables will in turn affect psychological well-being. The results will help establish causal factors in healthy adjustment and will provide normative data on the development of minority youth. These findings will be useful in developing ways to promote the development and psychological well-being of minority adolescents, a group at greater risk than White adolescents for a variety of mental health problems.